Keep getting booted on my iPad even though I have reset and redownloaded

I keep getting booted from the game when I try to go to other members city's.  i do not have much of a problem when i am in the market.  I have deleted all of my Tokyo, London and French buildings to lower my Population.  This seems to work, but i also have to put all my other stuff in storage to keep Population low.  This makes it very difficult for me to contribute to my group during the mayor Challenge and during the War challenge/